Means of feeding gyratory crushers



Sept. 22, 1942.

O. C. GRUENDER MEANS OF FEEDING GYRATORY CRUSHERS Filed Aug. 3, 1940 2 Sheets-Sheet l Sept 22, 1942- o. c. GRUENDER 2,296,280

MEANS OF FEEDING GYR'IOR-l"CRUSHERS` Filed Aug. 3, 1940 2 Sheets-Sheet 2 'Patented Sept. 22, 1942 ol-FICE MEANS F FEEDING GYRATORY CRUSHERS Oscar C. Gruender, Milwaukee, Wis., assigner to Nordberg Manutacturin Wis., a corporation of Claims.

My invention relates to an improvement in feeding means for gyratory Crushers and has for one' purpose'the provision of an improved apparatus for controlling the feed of material to a gyratory crusher.

Another purpose is the provision of improved feeding means which shall be integral with or directly associated with the crushinghead.

Another purpose is Vthe provision of a feeding means or feeding zone located above the crushing zone.

Another purpose is the provision of improved means whereby the movement and shape of the crushing head itself is effective to control the movement of material through a feed zone lo- Y cated immediately above the top of the crushing cavity. I

Another purpose is the provision of improved means for preventing the acceleration of the particles to be crushed whereby they enter the crushing zone at low or zero velocity.

Another purpose is the provision of `improved means for metering the feed of the gyratory crusher in which the crushing takes place below the metering zone with a sparsely filled crushing cavity, and without any support of the particles in the metering zone by the particles in the crushing cavity.

Another purpose is to care for the surplus material which is not permitted immediately to enter the crushing cavity, and to employ the mass of surplus material as a surge body. Other purposes will appear from time to time in the course of the specification and claims.

I illustrate my invention more or less diagrammatically in the accompanying drawings `wherein: I

Fig. 1 is a vertical axial section;

Fig, 2 is a similar partial section on an enlarged scale, illustrating the feeding zone at the closed side of the Crusher; and

Fig. 3 is a similar section illustrating the feeding zone at the open side of the crusher.

Like parts are indicated by like symbols throughout the specification and drawings.

Referring to the drawings, I indicates any suitable main frame, the details of which do not of themselves form part of the present invention. It is illustrated as having an outwardly extending top flange 2, which receives a supporting ring 3, having a screw threaded portion `4, to which is screw threaded the outer bowl wall 5. The bowl is shown as having an upwardly and` inwardly co'nic lower wall 6, and an upper upwardly and g Company, Milwaukee,

Wisconsin Application August 3, 1940, Serial No. 350,887

(c1. :z3-1o) a species of box structure, in which are webs 8, supporting locking bolts 9, with washers III and nuts II. I2 is a bowl liner having inwardly extending lugs I3, penetrating through apertures I4 in the bowl Wall 6, and held by the bolts 9, which may for example be U-bolts. l

IG are any suitable apertures in the bowl wall 1 `closed by any suitable closures I1. I8 is a superposed conic defiector conforming generally to the conicity of the bowl wall 1. isa generally cylindrical sleeve preferablyA with the main frame I and having an upwardly outward extension 2I. 22 is a sleeve rotatable within the bearing sleeve 20, and provided with a gear 23 located within the enlargement 2|, and in mesh, for example, with any suitable pinion 24, on a drive shaft 25, driven from any suitable power source not herein shown. for the enlargement 2|, which is provided with an upwardlyv spherical bearing member 21, adapted to receive a correspondingly formed spherical surface of the lower portion of the head 28.

25 is any suitable crushing mantle, held in position for example by a locking ring 30, screw threaded to the fixed locking member 3|,.Which is secured to the top of the head 28 as by bolts 1 32. 33 is any suitable upward extension of the outwardly conc wall 1, the three walls making 55 member 3|, to which may be secured any suitable feed support 34, on the top of which is illustrated a feed distributing plate 35, aligned with any suitable feed chute 36, mounted on the transverse members 31, which in turn are located in vertical supports 38, as by the adjusting nuts 39. 40 are any suitable springs adapted normally to hold the member 3 xed in position in relation to the main frame I. l

The details of the machine as so far described `do not of themselves form part of the present invention. It will be observed that the diameter of the feed distributing plate 35 is as` large as, or greater than, the diameter of the inlet to the crushing cavity defined by the upper edge of the bowl liner I2.

is an upwardly and inwardly conic deflector member, mounted upon or formed as a continuation of the locking nut 30. It will be observed that the opposed walls of the head and concave as above described define a relatively restricted cavity, the Walls of which, however, :dare apart to define an angle suci'ently great to prevent any crushing action.

Referring for example to Fig. 3, the line XY 'generally defines the top of the crushing cavity, and no effective crushing takes place above that line. The space above the `line yX-Y constitutes formed unitarily 26is a cover a feed restricting zone, and the space below the line XA-Y as defined by the opposite faces of the liner I2 and the mantle 29, constitutes a crushing zone. The head is provided with a shaft 50, which penetrates an eccentric aperture 5| in the rotated sleeve 22. Thus,in response to rotation of the drive shaft 25, the head is gyrated about a center indicated generally at 0. The effect of this gyration is to move the upper part of the head, including the members 30 and 45, toward and away from the upper part of the bowl liner I2, and the lower part of the conic deector sleeve I8. As will be clear from Fig. 1, the particles are dropped from the edge of the plate 35 upon the hopper vI8 and move downwardly and inwardly toward the head along a path substantially perpendicular to the face of the head. This movement is stopped by the head itself or by the particles or mass of particles which have previously built up upon the head and which move unitarily with the head when the head is gyrated. The movement of the head at that point is sufficient to move the particles upwardly and outwardly against their gravital tendency to flow into the crushing cavity. No particle can escape below the line X--Y of Fig. 3 until after it has been brought to a dead stop by engaging the head or the particles or mass of material resting upon the head. This stoppage may extend well up the hopper I8, as shown for example in Fig. 3, the

.mass of material in effect constituting an increase in the diameter of the head. Any particle which escapes from the bottom of the mass and passes the line X-Y has already been brought to a dead stop, and therefore enters the crushing cavity at zero velocity. After it escapes below the bottom of the mass or the line X-Y, it

slides downwardly along the face of the head until it is moved by the head for a crushing nip against the bowl I2. The crushing method thereafter carried out is substantially that described in the Symons Patent No. 1,537,564 and the Symons Reissue Patent No. 19,154.

Thus, in the actual crushing zone below the line X-Y, the particles are successively permitted to drop freely under gravity, because the mantle recedes from beneath the particles more readily than the particles can drop under gravity. Later the particles catch up with the mantle, 'or are received on the mantle as the mantle returns toward the bowl liner I2, and the particles are then given a crushing nip. This process continues step by step, the particles at each step falling freely under gravity away from the overhanging bowl and liner, and falling or being received by the mantle at a lower point, to receive a succeeding crushing nip.

In the form herein shown, the so-called shorthead cone crusher is indicated, in which the opposed faces of the bowl liner and mantle are generally parallel throughout most of the crushing cavity. In shorthead cone crushers it is exceedingly important to reduce the initial acceleration under gravity as far as possible, and to prevent particles from dropping into the crushing cavity. Otherwise the particles may fall gravitally farther into the crushing cavity than they should.

Referring particularly to Figs. 2 and 3, the circles indicated by Roman numerals indicate the positions of typical particles as they pass through the feed limiting zone. In following the movement of a particular particle from an initial position I, the particle will be carried up to the position II, approximately along an arc about the center 0. If the particles were able to fall freely from the position II, it would attain the position IV at the end of a half cycle of the head. But, as the head does not recede suiciently to allow the particles to fall this far, it will fall to the position III and slide generally to the position V. From the position V it will be carried by the movement of the head to the position VI, again along an approximate arc about the center IJ. As before, it will fall to the position VII instead of the position VIII, shown in dotted line, and will slide approximately to the position 1X, at which point it will be carried into the crushing zone, where it will be reduced according to the principle of crushing above described.

Each particle is thus stopped dead one or more times before it can penetrate the crushing cavity. And when it does penetrate or escape into the crushing cavity, it starts with substantially zero gravital acceleration.

In regard to the arcuate movement of the particle, in the first place, the friction between the mass and the head tends to prevent the material from sliding. In the second place, the 50 feeding zone angle is sufliciently large to allow the material to slip back toward the feed, or upwardly, as the liner I2 and the mantle 29 approach.

Referring for example to Fig. 2, the cross section -of the area A, B, C, D and E represents roughly the amount of material that is displaced upwardly toward the feed when the head moves to the closest position in which it is shown in Fig. 2. This displacement represents the amount of material fed to the crusher.

There is a breathing or agitating action of the material in the feed zone above the line X-Y, an alternate squeezing back of the mass and a feeding forward and upward of the mass, plus the accretions from the feed distributing plate 35. 'I'he mass of material which is being agitated but not crushed is defined at its lower face generally by the line X-Y. From this lower face of the mass, increments of material drop as the crushing space is opened and fall freely under gravity until they are caught by the head, and are thereafter given a crushing nip. In a real sense the crushing head meters the feed for the crushing zone, and the movement of the head, which is in the crushing cavity effective to impart a sequence of crushing impacts, is in the space above the crushing cavity effective to upward and outwardly move and agitate the mass of feed material without crushing .I have illustrated a crusher adapted primarily to carry out the crushing process or procedure of Patent No. 1,537,565, issued on May 12, 1925,

to Edgar B. Symons, and reissued on February 16, 1934, as No. 19,154. In these patents the material was sparsely fed to the crushing cavity, and separate mehanical means were employed for maintaining or limiting the feed to the volume necessary for the proper crushing effect. Separate mechanical means, such as a feed limiting plate, was employed. One purpose of the present invention is to provide metering means for limiting the feed and for maintaining the crushing method with the sparsely filled cavity which is characteristic of the above patents, while permitting the building of a mass of surplus material above the top of the crushing cavity.

I have illustrated a plate 35 mounted on the head 34 as means for feeding material to the hopper I8. However, it will be understood that the feed limiting plate 35 maybe omitted, and other means may be employed for directing the feed to the proper point.

It will be realized that,'whereas I have described and shown a practical and operative device, nevertheless many changes may be made in the size, shape, number and disposition of parts without departing from the spirit of my invention. I therefore wish my description and drawings to be taken as in a broad sense illustrative or diagrammatic, rather than as limiting me t my precise showing.

'I'he use and operation of my invention are as follows:

I employ my improved apparatus primarily, in connection with the crushing apparatus and method of the general type of the Symons Patent No. 1,537,565, issued on May 12, 1925, and reissued on February 16, 1934, as No. 19,154, and particularly in connection with the so-called Shorthead crusher. It is characteristic of these patents that the crushing cavity defined by the opposed cone and bowl is sparsely filled with material undergoing crushing, .the particles crushed at each crushing impact being .allowed to fall freely under gravity downwardly away from the bowl and toward the head until they are again picked up by the head and carried by the head toward the bowl for an ensuing crushing nip. In order to maintain this free fall under gravity, it is necessary to have the crushing cavity sparsely filled-that is to say, unlike the prior art gyratory crushers, the crushing cavity is very much larger in cubic content than the mass of particles undergoing crushing at any one time. It is highly important that over feeding be prevented, since otherwise the characteristic method and apparatus above described cannot be carried on. However, it may in practice be inconvenient to employ mechanical feed limiting means, such as limiting conveyors, feed limiting plates, or the like, to prevent over feeding. I have therefore provided an apparatus for causing the feed limiting or feed metering to be carried out by the shape and movement of the head itself, in connection with a feed limiting zone at the top of the sparsely filled crushing cavity. I illustrate, for example, as shown in detail in Figs. 2 and 3, a zone or space above the transverse line X-Y, which is at all times substantially filled with particles ready to undergo crushing. The space is defined by opposed walls of head and bowl, which Aare so inclined'in relation to each other and are so located in relation to the center of gyration that little or no crushing takes place. i

Referring to Fig l, it will be observed that the particles which escape over the edge of the plate 35 drop upon the hopper- I8. They are thereby directed downwardlyand inwardly toward the crushing head along a path substantially at right angles to the face of the crushing head. If we consider the movement taken by a single typical particle, it will be understood that the gap at the top of the crushing cavity of the Shorthead lowed in striking the head. Meanwhile it may be sliding somewhat down the head.

'Several alternations of movement may then take place, such as are shown dlagrammatically in Fig. 3, before the particle finally escapes past the line X--Y and is crushed in accordance with the Symons crushing method. It will be understood, however, that in the normal use of the device, the particles are fed in substantial quantities, and if more particles are fed than the head will permit to pass the line XY, which is normally the case,'thesurp1us material builds up or the cause of feed limitation, but is rather the crusher, as shown in Fig. l, is radially sufliciently result of the feed limiting action on the surplus material which cannot pass into the crushing zone. 'Ihe 'fact that it does so gather, as it does in practice, is proof that the method as above described is being carried out.

Assume that sufficient particles are fed to provide the surplus material shown in Figs. 2 and 3. The feed limiting `movement of the head is not thereby affected, andthe additional excess material is an advantage vrather than a disadi limiting effect Well up along the slope of the hopper I8. And the mass of material so formed can pulsate readily and crawl up and down along the face of the hopper I8 because the hopper face is smooth, and is substantially perpendicular to the face of the head. Furthermore, this mass of material serves as a feed evening surge bin. Thus, in the operation `of the machine the so-called bridge or mass of material might vary from a depth less than that shown in Figs. 2 and 3 to a depth which would carry the top of the mass halfway or more up the hopper I8. Under some circumstances the level may be even substantially higher.

It will be understood also that the particular feed directing means shown may be omitted. In other words, in place of the plate 35, some other means may be provided for dropping the material upon the hopper I8 in such fashion that it will move downwardly and inwardly toward the top of the head along a .path substantially at right angles to the face of the head. I claim:

1. In a gyratory crusher, an outwardly flaring head and an overhanging bowl, means for gyrating the head at a rate and through an excursion of sufficient length to cause the particles in the crushing cavity dened by the head and bowl to fall freely away from the face of the bowl under gravity at each crushing nip, and means for limiting the feed to the crushing cavity, which in'- cludes means for restricting the delivery of the particles to be crushed to movement along paths generally perpendicular to the face of the head, and for thereby bringing the particles so fed to a dead stop against the head or against material resting thereon, at the top of the crushing cavity, the upper portions of the head and bowl defining, at the topof the crushing cavity, a space. radially sufficiently restricted to limit the mass of stopped particles admitted to the top of the crushing cavity at each crushingwstroke to a volume no greater than the volume of crushed particles discharged from the bottom of the crushing cavity at each crushing stroke.

2. In a gyratory crusher, an .outwardly flaring head and an overhanging bowl, means for gyrating the head at a rate and through an excursion of suillcient length to cause the particles in the crushing cavity defined by the head and bowl to fall freely away from the face of the bowl under gravity at each crushing nip, and means for limiting the feed to the crushing cavity, which includes means for restricting the delivery of particles to be crushed to movement along paths generally perpendicular to the face of the head, and for thereby bringing the particles Vso fed to a dead stop against the head or against material resting thereon, at the top of the crushing cavity, the upper portions of the head and bowl deflning, at the top of the crushing cavity, a space radially sulciently restricted to limit the mass of stopped particles admitted to the top of the crushing cavity at each crushing stroke to a volume no greater than the volume of crushed particles discharged from the bottom of the crushing cavity at each crushing stroke, such means including a downwardly and inwardly inclined hopper, and means for delivering the particles'to be crushed to the face of said hopper a sufficient distance above its lower edge to impart gravltally to the particles sufcient speed to enable them to cross the gap between bowl and head and to strike the head generally at right angles to the face of the head.

3. In a gyratory crusher, an outwardly flaring head and an overhanging bowl, means for gyrating the head at a rate and through an excursion of sumcient length to cause the particles in the crushing cavity defined by the head and bowl to fall freely away from the face of the bowl under gravity at each crushing Knip, and means for limiting the feed to the crushing cavity, which includes means for restricting the delivery of the particles to be crushed to movement along paths generally perpendicular to the face of the head, and for thereby bringing the particles so fed to a dead stop against the head or ume of crushed particles discharged from the bottom of the crushing cavity at each crushing stroke, such means including a downwardly and inwardly inclined hopper, and means for. delivering the particles to be crushed to the face of said hopper a sufllcient distance above its lower L edge to impart gravitally to the particles sufficient speed to enable them `to cross the gap between bowl and head and to strike the head generally at right angles to the face of the head, including a distributing plate mounted on and gyrating with said head, the diameter of the plate exceeding the outside diameter of the top of the crushing cavity.

4. In a gyratory crusher, an outwardly flaring head and an overhanging bowl, means for gyrating the head at a rate and through an excursion of suillcient length to cause the particles in the crushing cavity defined by the head and bowl to fall freely away from the face of the bowl under gravity at each crushing nip, and means for limiting the feed to the crushing cavity, which includes means for restricting the delivery o'f the particles to be crushed to movement along paths generally perpendicular to the face of the head, and for thereby bringing the particles so fed to a dead stop against the head or against material resting thereon, at the top of the crushing cavity, the upper portions of the head and bowl defining, at the top of the crushing cavity, a space radially sulliciently restricted to limit the mass of stopped particles admitted to the top of the crushing cavity at each crushing stroke to a volume no greater than the volume of crushed particles discharged from the bottom of the crushing cavity at each crushing stroke, such means including a downwardly and inwardly inclined hopper, and means for delivering the particles to be crushed to the face of said hopper a suflicient distance above its lower edge to impart gravitally to the particles suflicient speed to enable them to cross the gap between bowl and head and to strike the head generally at right angles, including a distributing plate mounted on and gyrating with said head, the diameter of the plate exceeding the outside diameter of the top of the crushing cavity, the length of excursion of the head at the top of the crushing cavity being sumcient to move the excess particles above the crushing cavity upwardly and outwardly against their normal downward gravital movement.

5. In a gyratory crusher, an outwardly flaring head and an overhanging bowl, means for gyrating the head at a rate and through an excursion of suflicient length to cause the particles in the crushing cavity defined by the head and bowl to fall freely away from the face of the bowl under gravity at each crushing nip, and means for limiting the feed to the crushing cavity, which includes means for restricting the delivery of the particles to be crushed to movement along paths generally perpendicular to the face of the head, and for thereby bringing the particles so fed to a dead stop against the head or againstmaterial resting thereon, at the top of the crushing cavity, the upper portions of the head and bowl dening, at the top of the crushing cavity, a space radially sufficiently restricted to limit the mass of stopped particles admitted to the top of the crushing cavity at each crushing stroke to a volume no greater than the volume of crushed particles discharged from the bottom of the crushing cavity at each crushing stroke, the stroke of the head at the top of the crushing cavity being generally of the same length as the radial width of the top of the crushing cavity at the point of closest approach 0f head to bowl.

OSCAR C. GRUENDER. 

